Cycloamide-transition metal complexes and bleach catalysts

ABSTRACT

The invention provides a bleaching catalyst and a bleaching composition having a sufficient bleaching effect even at low temperatures and being excellent in an effect of preventing color migration in fibers with less bleach of dyes and less damage to fibers. The invention provides a cyclic amide transition metal complex (1), a bleaching catalyst containing the same, and a bleaching composition containing the bleaching catalyst and a peroxy bleaching agent selected from hydrogen peroxide and a peroxide or an organic peracid generating hydrogen peroxide in an aqueous solution.  
                 
 
wherein R 1  to R 6  represent H, a C 1-16  hydrocarbon or perfluoroalkyl group or a halogen atom, R 7  represents a C 1-18  alkylene or perfluoroalkylene group, A represents a group having 1 to 3 quaternary ammonium groups substituted with an alkyl group or linked with an alkylene group, or a heterocyclic aromatic quaternary cation group, or the like, M represents a transition metal, L represents a ligand, and Q represents a counterion.

FIELD OF THE INVENTION

The present invention relates to a cyclic amide transition metal complexhaving an ability to activate bleaching and a bleaching catalystcontaining the same, as well as a bleaching composition having anexcellent bleaching effect even at low temperatures and being alsoexcellent in an effect of preventing color migration in fibers with lessbleach of dyes and less damage to fibers.

BACKGROUND OF THE INVENTION

Use of a peroxy bleaching agent in washing, such as hydrogen peroxideetc., belongs to known technology. This peroxy bleaching agent is usedat high temperatures and can bleach stains with tea, coffee, wine, fruitetc. However, the bleaching effect of the peroxy bleaching agent issignificantly lowered at 60° C. or less, and therefore, use of atransition metal complex having an ability to activate bleaching incombination with the peroxy bleaching agent has been examined; forexample, JP-B 7-65074 discloses a manganese complex with cyclicpolyamine as a ligand, JP-A 11-507689 discloses a cobalt ammine complex,JP-A 8-67687 and JP-A 11-515049 disclose a Schiff base derivativecomplex of manganese or cobalt, and WO-A 95/34628 and WO-A 97/48710disclose an iron complex with a pyridyl methylamine derivative as aligand. However, these complexes fail to achieve a sufficient bleachingeffect on polyphenol-based stains such as stains with tea, and bringabout problems such as decolorization of dyes and damage to fibers.

It is important for a factor for allowing a transition metalcomplex-containing bleaching composition to exhibit a bleaching activitythat the complex itself is stable in the form of an aqueous bleachsolution, and upon reacting with a hydrogen peroxide source, forms acertain kind of oxidized active species to react with stains. Inaddition, whether or not the catalyst can approach a subject ofbleaching (fibers (cloth) and rigid surfaces of glass, pottery etc.) isalso mentioned as another important factor. Both the subject ofbleaching and a majority of stains are negatively charged (anionic), andthe peroxides such as hydrogen peroxide sources are also anionic, butfor preferable electrostatic interaction, it is advantageous that thecatalyst itself is cationic (JP-A 1-97267). Actually, the manganesecomplex described in JP-B 7-65074 and the cobalt complex described inJP-A 11-507689 are designed to be cationic complexes so as to easilyapproach fibers (cloth). However, the bleaching compositions containingsuch complexes have problems such as decolorization of dyes and damageto fibers as described above.

On the other hand, a large cyclic tetramide transition metal complexdescribed in WO-A 98/03625 is excellent in an ability to bleach a widevariety of stains with tea, wine, fruit etc. in aqueous solution, but ispoor in an ability to bleach stains adhering to a cloth. An estimatedreason for this insufficient ability is that this complex is anionic andthus hardly approaches a negatively charged cloth.

Further, WO-A 98/58735 discloses a compound having a pyridine skeleton,and WO-A 99/64156 discloses a compound having a pyridinium ring, butthese compounds are different in structure from the compound of thepresent invention, and do not exhibit an excellent effect achieved bythe present invention.

SUMMARY OF THE INVENTION

The present invention provides a bleaching catalyst and a bleachingcomposition having a sufficient bleaching effect even at lowtemperatures and excellent in an effect of preventing color migration infibers with less bleach of dyes and less damage to fibers.

The present invention provides a cyclic amide transition metal complexrepresented by formula (1) (hereinafter referred to as cyclic amidetransition metal complex (1)), a bleaching catalyst containing the same,and a bleaching composition containing (a) a bleaching catalystcontaining the cyclic amide transition metal complex (1) and (b) aperoxy bleaching agent selected from hydrogen peroxide and a peroxide oran organic peracid generating hydrogen peroxide in an aqueous solution.

wherein R¹, R², R³, R⁴, R⁵ and R⁶ are the same or different, and eachrepresents a hydrogen atom, a C1 to C16 hydrocarbon or perfluoroalkylgroup or a halogen atom, R⁷ represents an optionally substituted C1 toC18 alkylene or perfluoroalkylene group, A represents a group having 1to 3 quaternary ammonium groups substituted with a linear or branchedalkyl group or linked with a linear or branched alkylene group, a cyclicquaternary ammonium group, or a heterocyclic aromatic quaternary cationgroup which may be substituted with a linear or branched alkyl group, Mrepresents a transition metal, L represents a ligand, and Q representsan arbitrary counterion equilibrated stoichiometrically with an electriccharge of the compound.

DETAILED DESCRIPTION OF THE INVENTION

In the cyclic amide transition metal complex (1) in the presentinvention, the groups represented by R¹, R², R³, R⁴, R⁵ and R⁶ include ahydrogen atom, a C1 to C16 alkyl or a perfluoroalkyl group or a halogenatom such as F, Br, Cl or I, but from the viewpoint ofoxidation-resisting stability and bleaching activity of the catalyst,each of the groups is preferably a methyl group, a fluorine atom or aperfluoroalkyl group, more preferably a methyl group.

R⁷ is preferably a C1 to C18 linear or branched alkylene orperfluoroalkylene group, specifically an alkylene group such asn-ethylene group, n-propylene group, n-butylene group, n-pentylenegroup, n-hexylene group, n-heptylene group, n-octylene group, n-nonylenegroup, n-decylene group, n-undecylene group and n-dodecylene group or aperfluoroalkylene group such as n-perfluorohexylene group, morepreferably a —(CH₂)_(n)— group (n is an integer of 1 to 18),particularly preferably a C3 to C8 linear alkylene group such asn-propylene group, n-butylene group, n-pentylene group, n-hexylenegroup, n-heptylene group and n-octylene group.

A has the meaning defined above, wherein the group having 1 to 3quaternary ammonium groups substituted with a linear or branched alkylgroup or linked with a linear or branched alkylene group includes aquaternary ammonium group substituted with a C1 to C18 alkyl group, agroup having 2 to 3 quaternary ammonium groups substituted with a C1 toC3 alkyl group and linked with a C1 to C18 alkylene group, etc. Thecyclic quaternary ammonium group includes a pyrrolidinium group,piperidinium group etc. The heterocyclic aromatic quaternary cationgroup which may be substituted with a linear or branched alkyl groupincludes a pyridinium group, pyrazinium group, pyrimidinium group etc.,each of which may be substituted with a C1 to C18 alkyl group. Amongthese groups, —N⁺(CH₃)₂(C_(m)H_(2m+1)) (m is an integer of 1 to 18),—N⁺(CH₃)₂—(CH₂)_(p)—N⁺(CH₃)₃ (p is an integer of 1 to 18) and apyridinium group are preferable, and a trimethyl ammonium group[—N⁺(CH₃)₃], a dimethyl-octyl ammonium group [—N⁺(CH₃)₂(C₈H₁₇)], adimethyl-dodecyl ammonium group [—N⁺(CH₃)₂(C₁₂H₂₅)], adimethyl-trimethyl ammoniopropyl ammonium salt[—N⁺(CH₃)₂—(CH₂)₃N⁺(CH₃)₃] and a pyridinium group are more preferable.

M includes Mn, Fe, Co, Ni, Cu and Zn, among which Fe, Mn and Co arepreferable in respect of bleaching activity, and Fe, particularlyFe(III), is preferable in respect of safety. L represents a ligand whichis specifically water, a lower alcohol (methanol, ethanol etc.), asolvent molecule such as acetonitrile, a halogen atom such as Cl, Bretc., an amine molecule such as pyridine, imidazole, trimethylamineetc., or the like, among which water, a lower alcohol and Cl arepreferable. Q represents an arbitrary counterion equilibratedstoichiometrically with an electric charge of the compound, and includesa counter anion such as Cl⁻, Br⁻, I⁻, NO₃ ⁻, NCS⁻, ClO₄ ⁻, OH⁻ etc. whenthe charge of the complex as a whole is positive, or an alkali metal ionsuch as Li⁺, Na⁺, K⁺ etc., an alkaline earth metal ion such as Mg²⁺,Ca²⁺ etc., a counter cation such as alkyl ammonium ion etc. when thecharge of the complex as a whole is negative.

Examples of the cyclic amide transition metal complex (1) includecompounds represented by the following chemical structures. In thestructures, the ligand L and counterion Q are omitted.

A general method of synthesizing the cyclic amide transition metalcomplex (1) of the present invention is shown below. For example, a Fecomplex of formula (1) wherein M is Fe can be synthesized by a methodshown in the following scheme 1 using a macrolinker represented byformula (2) and a heterocyclic aromatic diamine represented by formula(4) as the starting material, as described by Collins, T. J. et al. inJ. Am. Chem. Soc., 120, 11540-11541 (1998), or in WO 9858735.

wherein R¹, R², R³, R⁴, R⁵, R⁶ and n have the same meanings as definedabove, X represents a halogen atom, and Me represents a methyl group.

That is, a macrolinker represented by formula (2), obtained by couplinga-aminocarboxylic acid at about 70° C. in pyridine with malonic aciddichloride substituted at the α-position is dehydrated in pyridine(under reflux) with about 2.4 equivalents of pivaloyl chloride to forman oxazolone represented by formula (3). One equivalent of2,3-diaminopyridine represented by formula (4) is added to close thering, and the sample is refluxed in pyridine for 3 days to give a largecyclic tetramide represented by formula (5). The resulting large cyclictetramide is reacted with a large excess of α,ω-dihalogenated alkyl at100° C. for 6 days, whereby a large cyclic tetramide converted intoω-halogenoalkyl pyridinium represented by formula (6) is obtained. Then,the halogen group in this large cyclic tetramide is converted into atertiary ammonium group by reaction, for example, with a tertiary aminesuch as trimethylamine, whereby a tetramide represented by formula (7)is obtained. Finally, an amide proton is eliminated from the tetramiderepresented by formula (7) in tetrahydrofuran (THF) with a base (about 6equivalents) such as bis(trimethylsilyl)amide lithium to generate anamide anion. A large cycle tetraamide Fe complex modified withω-quaternary ammonioalkyl pyridinium, represented by formula (1-1), canbe obtained, for example, by adding about 1.5 equivalents of FeCl₃.

In the cyclic amide transition metal complex obtained in the mannerdescribed above, the covalence of the transition metal may be regulatedif necessary by an oxidizing agent, or the counterion or axial ligand ofthe complex may be exchanged with another by a known method.

A bleaching catalyst containing the cyclic amide transition metalcomplex (1) in the present invention (referred to hereinafter ascomponent (a)) has an excellent effect by blending it with a peroxybleaching agent (referred to hereinafter as component (b)) selected fromhydrogen peroxide, a peroxide or an organic peracid generating hydrogenperoxide in an aqueous solution.

The content of the component (a) in the bleaching composition of theinvention containing the components (a) and (b) is preferably 0.0001 to10% by weight, more preferably 0.0001 to 3% by weight. The content ofthe component (b) is preferably 0.01 to 99% by weight, more preferably0.01 to 80% by weight. The ratio by weight of the component (b) to thecomponent (a), that is, (b)/(a), is preferably 10 to 100,000, morepreferably 10 to 50,000, from the viewpoint of the effective action ofthe component (a) as a bleaching catalyst to exhibit excellent bleachingperformance.

The component (b) is preferably hydrogen peroxide or a peroxidegenerating hydrogen peroxide in an aqueous solution. The peroxidegenerating hydrogen peroxide in an aqueous solution includes sodiumpercarbonate, a sodium tripolyphosphate/hydrogen peroxide adduct, asodium pyrophosphate/hydrogen peroxide adduct, a urea/hydrogen peroxideadduct, sodium perborate.1 H₂O, sodium perborate.4 H₂O, sodium peroxideand calcium peroxide, among which sodium percarbonate, sodiumperborate.1 H₂0 and sodium perborate.4 H₂O are preferable.

The bleaching composition of the present invention may be in a powderyor liquid form, and besides the essential ingredients described above,an alkali, a surfactant, a sequestering agent etc. can be contained.Preferable examples of the alkali include sodium carbonate, potassiumcarbonate etc. The surfactant is preferably an anionic surfactant or anonionic surfactant, and the anionic surfactant includes sodium alkylbenzene sulfonate, sodium alkyl sulfate etc. having a C10 to C18 alkylgroup, and the nonionic surfactant includes various polyoxyethylenealkyl ethers. The content of the surfactant in the bleaching compositionof the present invention is preferably 50 wt % or less, more preferably0.5 to 40 wt %.

The sequestering agent includes phosphate, phosphonocarboxylate,polyacrylate etc. The content of the sequestering agent in the bleachingcomposition of the present invention is preferably 30 wt % or less, morepreferably 0.1 to 20 wt %, from the viewpoint of the bleaching effect.

A re-contamination inhibitor, a filler, an enzyme, a fluorescentbrightener, a dye, a pigment, a perfume etc. can be added if necessaryto the bleaching composition of the present invention.

The bleaching composition of the present invention can be added to apowdery or liquid detergent for cloth, a detergent for hard surface, adetergent for automatic dishwashers, a detergent for false teeth, etc.,to confer bleach performance or an ability to prevent color migration.Further, the bleaching composition of the present invention can be usedin various industrial applications such as hair bleach and bleach ofwood pulp and salvaged paper.

The bleaching catalyst and bleaching composition of the presentinvention have a sufficient bleaching ability even at low temperaturesof 30° C. or less and do not cause damage to fibers or bleach of dyes.

The bleaching catalyst and bleaching composition of the presentinvention have an excellent bleaching effect even at low temperaturesand are excellent in an effect of preventing color migration in fiberswith less bleach of dyes and less damage to fibers.

EXAMPLES Production Example 1

A cyclic Fe complex represented by formula (I-a-1) (hereinafter, alsoreferred to as cyclic Fe complex (I-a-1)) was synthesized according tothe method in scheme 1.

(a) Synthesis of Large Cyclic Tetramide (5-1)

4.5 g (14.9 mmol) macrolinker of the above formula (2) wherein R¹ to R⁶each represent a methyl group was dried at 100° C. for 2 hours undervacuum, and 130 ml anhydrous pyridine and 4.5 mL (36 mmol) pivaloylchloride were added thereto and heated under reflux at 115° C. for 24hours (conversion into oxazolone). 1.56 g (14.4 mmol) of2,3-diaminopyridine was added thereto and heated for 3 days underreflux, and 15 mL deionized water was added thereto and stirred for 24hours at 100° C. After the solvent was distilled away, a black viscousproduct was obtained. This viscous product was dissolved in a solutionof 50 ml water/20 ml ethanol containing 3.6 g (34 mmol) Na₂CO₃, stirredfor 30 minutes and adjusted to pH 9 with Na₂CO₃. The solvent wasdistilled away, 100 ml ethanol was added to the black viscous product,and precipitated inorganic salts were removed by filtration. The ethanolin the resulting filtrate was distilled away, whereby black solids wereobtained. The solids were dispersed in acetonitrile, stirred for 13hours and filtered to give a dark brown filtrate. To extract the wholeof the desired product, this operation was repeated several times. Theresulting filtrates were combined and the solvent was distilled away,whereby brown solids were obtained. The solids were triturated inpetroleum ether, filtered and dried to give about 5 g brown powder.

The brown powder was dissolved in a mixed solvent of 25 ml ethanol and100 ml water, and the solvent was gradually distilled away underheating, to precipitate black viscous insolubles. A filtrate obtained byremoving the insolubles was concentrated to give about 3.2 g blackviscous product. When 5 ml methanol was added thereto, white crystalswere obtained. By recovery by filtration and subsequent drying, 530 mg(yield 9.5%) of the title compound of formula (5) wherein R¹ to R⁶eachrepresent a methyl group was obtained in the form of white crystals.

Rf 0.28 (CH₂Cl₂/MeOH=95/5).

IR (KBr, cm⁻¹): 3355, 3315 (NH), 2993, 2947 (CH), 1701, 1635 (C═O).

¹H-NMR (δppm, DMSO): 1.42 (s, 6H), 1.44 (s, 6H), 1.46 (s, 6H), 7.28 (dd,1H), 7.78 (s, 1H), 7.83 (s, 1H), 7.97 (d, 1H), 8.21 (d, 1H), 8.24 (s,1H), 8.85 (s, 1H).

¹³C-NMR (δppm, DMSO): 22.02, 24.41, 25.19, 50.65, 57.59, 57.65, 121.96,128.91, 132.64, 142.75, 144.41, 171.96, 172.82, 173.26, 173.58.

(b) Synthesis of Large Cyclic Tetramide (6-1) Modified Withω-Halogenoalkyl Pyridinium

1,6-Dibromohexane, 5 ml (32.5 mmol, 244 equivalents), was added to thelarge cyclic tetramide (5-1), 50 mg (0.133 mmol), obtained in (a), andthe mixture was aged at 100° C. for 6 days while the reaction wasmonitored with TLC. The reaction product was purified by silica gelcolumn chromatography, to give 54 mg (yield 66%) of the title compoundof formula (6) wherein R¹ to R⁶ each represent a methyl group, n is 6,and X is Br, was obtained in the form of white powder.

Rf 0.45 (CH₂Cl₂/MeOH=95/5).

¹H-NMR (δppm, CDCl₃): 1.32 (m, 2H), 1.48 (m, 2H), 1.52 (s, 6H) 1.608 (s,6H), 1.614 (s, 6H), 1.83 (m, 4H), 3.4 (t, 2H), 4.08 (t, 2H), 6.30 (s,1H), 6.84 (dd, 1H), 7.33 (dd, 1H), 7.54 (s, 1H), 8.74 (dd, 1H), 9.22 (s,1H).

¹³C-NMR (δppm, CDCl₃): 23.13, 25.71, 25.84, 27.62, 28.79, 32.30, 33.46,50.54, 55.35, 58.45, 59.32, 114.96, 125.95, 131.87, 133.01, 151.67,172.09, 173.66, 174.01, 175.99.

(c) Synthesis of Cyclic Fe Complex (I-a-1) Ligand

The large cyclic tetramide modified with ω-halogenoalkyl pyridinium(6-1), 47 mg (0.076 mmol), obtained in (b) was dissolved in 20 mlmethanol, and then 100 μl (0.47 mmol, 8 equivalents) of 30% aqueoustrimethylamine was added thereto and the mixture was aged at 60° C.While the reaction was monitored with TLC, the mixture was aged for 2days during which 30% aqueous trimethylamine was added thereto whenevernecessary (total: 56 equivalents). After the solvent was distilled away,the product was purified by re-crystallization from adichloromethane/ethyl ether system to give the title compound, 47 mg(yield 92%), in the form of white powder.

IR (KBr, cm⁻¹): 2981, 2937 (CH), 1678 (C═O).

¹H-NMR (δppm, D₂O): 1.21 (bs, 4H), 1.38 (s, 12H), 1.44 (s, 6H), 1.60 (t,2H), 1.69 (t, 2H), 2.93 (s, 9H), 3.12 (t, 2H), 4.02 (t, 2H), 7.23 (dd,1H), 8.01 (d, 1H), 8.33 (d, 1H)

¹³C-NMR (δppm, D₂O): 22.23, 25.21, 25.33, 28.77, 51.12, 52.87, 55.76,58.44, 58.81, 66.54, 118.71, 130.83, 135.99, 137.97, 153.11, 173.81,174.39, 176.34, 178.2.

(d) Synthesis of Cyclic Fe Complex (I-a-1)

38 mg (0.056 mmol) of the ligand obtained in (c) was dissolved in 10 mLanhydrous THF, then charged with 0.33 mL (6.0 equivalents) of a THFsolution of 1.0 M bistrimethylsilylamide lithium at room temperature andaged for 10 minutes. Thereafter, the mixture was charged with 13.5 mg(about 1.5 equivalents) of FeCl₃ powder and stirred in a nitrogenatmosphere at room temperature for 4 hours. The resulting crystals werefiltered and dried to give the title compound, 33.6 mg (yield 99%), inthe form of dark yellow powder.

UV (in distilled water) λmax: 267 nm (ε=7424), 318 nm (ε=6725)

IR (KBr, cm⁻¹): 1630 (amide C═O).

Production Example 2

A cyclic Fe complex represented by formula (I-b-1) (hereinafter, alsoreferred to as cyclic Fe complex (I-b-1)) was synthesized according tothe method in scheme 1.

(a) Synthesis of Cyclic Fe Complex (I-b-1) Ligand

The large cyclic tetraamide modified with ω-halogenoalkyl pyridinium(6-1), 101 mg (0.164 mmol), obtained in (b) in Production Example 1 wasdissolved in 10 ml isopropyl alcohol, and 337 μl (1.64 mmol, 10equivalents) of N,N-dimethyloctylamine was added thereto, and themixture was reacted at 70° C. for 69 hours. After the solvent wasdistilled away, the residues were washed with ethyl ether to remove anexcess of N,N-dimethyloctylamine to give 135 mg (0.174 mmol, yield 106%)of the title compound in the form of white powder.

Rf 0.00 (MeOH only), 0.66 (2% aq. KNO₃/MeCN=1/1).

¹H-NMR (δppm, D₂O): 0.696 (t, 3H), 1.109 (m, 6H), 1.182 (m, 8H), 1.375(s, 12H), 1.441 (s, 6H), 1.548 (m, 4H), 1.681 (m, 2H), 2.854 (s, 6H),3.071 (m, 4H), 4.013 (t, 2H), 7.228 (dd, 1H), 8.01 (d, 1H), 8.33 (d,1H).

IR (KBr, cm⁻¹): 2927, 2858 (CH), 1685, 1630 (amide C═O).

(b) Synthesis of Cyclic Fe Complex (I-b-1)

100.4 mg (0.1293 mmol) ligand obtained in (a) was dissolved (uniformlydissolved) in 10 mL anhydrous THF and then charged with 705 μL (6.0equivalents) of a THF solution of 1.1 M bis(trimethylsilyl)amide lithiumin a nitrogen stream at room temperature followed by aging for 30minutes (pale yellow uniform solution). Thereafter, the solution wascharged with 26.8 mg (about 1.5 equivalents) of FeCl₂ and stirred atroom temperature for 21 hours in a nitrogen atmosphere at roomtemperature (dark brown solution with insolubles). For oxidizing Fe(II)into Fe(III), the solution was bubbled with oxygen for 2 hours. Thecrystals were recovered by filtration and then dissolved in methanol,and insolubles were removed by a membrane filter. The filtrate wasconcentrated and dried to give 175 mg dark brown viscous product. Theresulting brown solids were subjected to gel filtration (elution withMeOH from Sephadex LH20), whereby low-molecular impurities were removed,and the eluate was concentrated and dried to give the title compound, 48mg (yield 53%), in the form of dark brown solids.

UV (in distilled water): λmax: 269 nm (ε=9849), 316 nm (ε=9957)

IR (KBr, cm⁻¹): 2927, 2858 (CH), 1630 (amide C═O)

Production Example 3

A cyclic Fe complex represented by formula (I-c-1) (hereinafter, alsoreferred to as cyclic Fe complex (I-c-1)) was synthesized according tothe method in scheme 1.

(a) Synthesis of Cyclic Fe Complex (I-c-1) Ligand

36 mg (0.058 mmol) of the large cyclic tetraamide modified withω-halogenoalkyl pyridinium (6-1), obtained in (b) in Production Example1, was dissolved in 15 ml isopropyl alcohol, and 319 μl (1.159 mmol, 20equivalents) of N,N-dimethyldodecylamine was added thereto, and themixture was reacted at 80° C. for 43 hours. After the solvent wasdistilled away, the residues were washed with ethyl ether to remove anexcess of N,N-dimethyldodecylamine to give 47 mg (0.056 mmol, yield 96%)of the title compound in the form of white powder.

Rf 0.00 (MeOH only), 0.72 (2% aq. KNO₃/MeCN=1/1).

¹H-NMR (δppm, D₂O): 0.726 (t, 3H), 1.116 (m, 18H), 1.157 (m, 4H), 1.350(s, 6H), 1.394 (s, 6H), 1.413 (s, 6H), 1.523 (m, 4H), 1.625 (m, 2H),2.881 (m, 6H), 3.092 (m, 4H), 4.006 (m, 2H), 7.140 (dd, 1H), 7.958 (d,1H), 8.36 (d, 1H).

IR (KBr, cm⁻¹): 2925, 2854 (CH), 1685, 1630 (amide C═O)

(b) Synthesis of Cyclic Fe Complex (I-c-1)

35.6 mg (0.0427 mmol) ligand obtained in (a) was dissolved (uniformlydissolved) in 7 mL anhydrous THF and then charged with 233 μL (6.0equivalents) of a THF solution of 1.1 M bis(trimethylsilyl)amide lithiumin a nitrogen stream at room temperature followed by aging for 10minutes (pale yellow uniform solution). Thereafter, the solution wascharged with a solution of 10.4 mg (about 1.5 equivalents) of FeCl₃ in 1ml anhydrous THF and stirred at room temperature for 4 hours in anitrogen atmosphere (dark brown solution with insolubles) The crystalswere recovered by filtration and then dissolved in methanol, andinsolubles were removed by a membrane filter. The filtrate wasconcentrated and dried to give 12.6 mg brown solid (yield 39%).

Rf 0.38 (2% aq. KNO₃/MeCN=1/1).

UV (in distilled water): λmax: 267 nm (ε=6389), 322 nm (ε=4843)

IR (KBr, cm⁻¹) 2927, 2856 (CH), 1630 (amide C═O)

Production Example 4

A cyclic Fe complex represented by formula (I-d-1) (hereinafter, alsoreferred to as cyclic Fe complex (I-d-1)) was synthesized according tothe method in scheme 1.

(a) Synthesis of Large Cyclic Tetraamide Modified With ω-HalogenoalkylPyridinium (6-2)

15 ml (148 mmol) 1,3-dibromopropane was added to the large cyclictetraamide (5-1), 137 mg (0.365 mmol), obtained in (a) in ProductionExample 1, and while the reaction was monitored with TLC, the mixturewas aged at 60° C. for 5 days. The reaction product was purified bysilica gel column chromatography to give 98 mg (0.170 mmol, yield 47%)of the title compound of formula (6) wherein R¹ to R⁶ each represent amethyl group, n is 3, and X is Br, was obtained in the form of whitepowder.

Rf 0.38 (CH₂Cl₂/MeOH=95/5).

¹H-NMR (δppm, CDCl₃): 1.51 (s, 6H), 1.605 (s, 6H), 1.614 (s, 6H), 2.37(m, 2H), 3.34 (t, 2H), 4.30 (t, 2H), 6.32 (s, 1H), 6.86 (dd, 1H), 7.41(dd, 1H), 7.51 (s, 1H), 8.74 (dd, 1H), 9.19 (s, 1H).

¹³C-NMR (δppm, CDCl₃) 23.27, 25.88, 26.12, 29.79, 30.91, 50.77, 53.80,58.66, 59.530, 115.31, 126.69, 132.68, 133.31, 151.89, 172.27, 173.90,174.21, 176.40.

(b) Synthesis of Cyclic Fe Complex (I-d-1) Ligand

The large cyclic tetraamide modified with 77 mg (0.1334 mmol) ofω-halogenoalkyl pyridinium (6-2), obtained in (a), was dissolved in 9 mlof isopropyl alcohol and 274 μl (1.334 mmol, 10 equivalents) ofN,N-dimethyloctylamine was added thereto. The mixture was reacted at 60°C. for 70 hours. After the solvent was distilled away, the residues werewashed with ethyl ether to remove an excess of N,N-dimethyloctylamine togive white powder. The resulting colorless solids were purified bysilica gel column chromatography (solvent: (1) MeOH→(2) 2% aq.KNO₃/MeCN=1/1). A purified product containing KNO₃ was dissolved inethanol, and insolubles were removed as inorganic salts. As de-saltingoperation, gel filtration (elution with MeOH from Sephadex LH20) wasconducted. 72 mg (0.0977 mmol, yield 73%) of the title compound wasobtained in the form of white solids.

Rf 0.00 (MeOH only), 0.63 (2% aq. KNO₃/MeCN=1/1).

¹H-NMR (δppm, D₂O): 0.695 (t, 3H), 1.12 (m, 10H), 1.366 (s, 6H), 1.387(s, 6H), 1.434 (s, 6H), 1.46 (m, 2H), 2.201 (m, 2H), 2.894 (s, 6H), 3.10(m, 2H), 3.16 (m, 2H), 4.10 (t, 2H), 7.25 (dd, 1H), 8.00 (dd, 1H), 8.39(dd, 1H).

IR (KBr, cm⁻¹): 2929, 2858 (CH), 1685, 1630 (amide C═O).

(c) Synthesis of Cyclic Fe Complex (I-d-1)

55.6 mg (0.0757 mmol) ligand obtained in (b) was dissolved (uniformlydissolved) in 5 ml anhydrous THF and then charged with 413 μL (6.0equivalents) of a THF solution of 1.1 M bis(trimethylsilyl)amide lithiumin a nitrogen stream at room temperature followed by aging for 5 minutes(yellowish brown→dark brown). Thereafter, the solution was charged witha solution of 18.4 mg (about 1.5 equivalents) of FeCl₃ in 1 ml anhydrousTHF and stirred at room temperature for 4 hours in a nitrogen atmosphere(dark brown solution with insolubles) The crystals were recovered byfiltration and then subjected to gel filtration (elution with MeOH fromSephadex LH20), whereby low-molecular impurities were removed, and theeluate was concentrated and dried to give the title compound, 30 mg(yield 60%), in the form of dark brown solids.

UV (in distilled water): λmax: 264 nm (ε=12299), 336 nm (ε=7054)

IR (KBr, cm⁻¹): 2978, 2931, 2871 (CH), 1626 (amide C═O).

Examples 1 to 4 and Comparative Examples 1 to 2

The cyclic Fe complex (I-a-1) obtained in Production Example 1, thecyclic Fe complex (I-b-1) obtained in Production Example 2, the cyclicFe complex (I-c-1) obtained in Production Example 3 and the cyclic Fecomplex (I-d-1) obtained in Production Example 4 were used to measurebleaching performance by the following method. Bleaching performance wasmeasured in the same manner by using a Fe—HM-DCB complex represented byformula (8) (complex described in WO9803625) as a comparative catalystor without using any bleaching catalyst. The results are shown in Table1.

<Method 1 of Measuring Bleaching Performance>(1) Preparation of a Dry Tea Extract Powder

10 g commercial tea leaves (Lipton) were extracted with 400 g hot water(90° C.) and then the tea leaves were freeze-dried. 2.53 g dark brownpowder was obtained as dry tea extract powder.

(2) Measurement of Bleaching Performance

As a subject of bleaching, the dry tea extract powder was added at aconcentration of 200 ppm to 10 ml of 0.05% aqueous sodium carbonate, andthe bleaching catalyst was added at a concentration of 5 ppm and further35% aqueous hydrogen peroxide was added at a concentration of 0.04%H₂O₂, to bleach the aqueous tea solution at 25° C. The aqueous teasolution before bleach (before addition of the aqueous hydrogenperoxide) and the aqueous solution after bleach treatment for 5 minuteswere measured for their absorbance at 420 nm with a UV-VIS measuringinstrument (HITACHI U-3300), and the degree of bleach was calculatedaccording to the following equation:Degree of bleach (%)=(1−absorbance after bleaching treatment/absorbancebefore bleaching treatment)×100 TABLE 1 Degree of bleach Bleachingcatalyst (%) Example 1 Cyclic Fe complex (I-a-1) in 85 productionexample 1 Example 2 Cyclic Fe complex (I-b-1) in 86 production example 2Example 3 Cyclic Fe complex (I-c-1) in 84 production example 3 Example 4Cyclic Fe complex (I-d-1) in 80 production example 4 ComparativeFe-HM-DCB complex 71 example 1 of formula (8) Comparative Not added 6example 2

Examples 5 to 8 and Comparative Examples 3 to 4

The cyclic Fe complex (I-a-1) obtained in Production Example 1, thecyclic Fe complex (I-b-1) obtained in Production Example 2, the cyclicFe complex (I-c-1) obtained in Production Example 3 and the cyclic Fecomplex (I-d-1) obtained in Production Example 4 were used to measurebleaching performance by the following method. Bleaching performance wasalso measured in the same manner by using a Fe—HM-DCB complexrepresented by formula (8) (complex described in WO9803625) as acomparative catalyst or without using any bleaching catalyst. Theresults are shown in Table 2.

<Method 2 of Measuring Bleaching Performance>

(1) Preparation of a Cloth Stained With Tea

80 g Nitto Tea (yellow package) was boiled in 3 L deionized water for 15minutes and filtered through a destarched, bleached cotton cloth. Acotton cloth was dipped in this solution, boiled therein for 15 minutesand then left for 2 hours. Then, the cloth was removed, air-dried andwashed with water until the wash became uncolored, and then the clothwas dehydrated, pressed and subjected as a tea-stained cloth of 4×4 cmto an experiment.

(2) Measurement of Bleaching Performance

As a subject of bleaching, the tea-stained cloth prepared by the abovemethod was dipped in 5 ml aqueous sodium carbonate (0.05%), and then0.025 mg bleaching catalyst (solution concentration 5 ppm) and 35%aqueous hydrogen peroxide were added such that the concentration of H₂O₂in the solution was 0.4%, and the stained cloth was subjected tobleaching treatment under the condition of 25° C./30 minutes. Afterbleaching treatment, the stained cloth was washed with water and dried,and the resulting stained cloth after bleaching and washing, the stainedcloth before bleaching, and the original cotton cloth were measured fortheir reflectance at 460 nm with a UV-VIS measuring instrument (HITACHIU-3300), and the degree of bleach was determined according to thefollowing formula:Degree of bleach (%)=(reflectance after bleaching andwashing−reflectance before bleaching)/(reflectance of the originalcloth−reflectance before bleaching)×100 TABLE 2 Degree of bleachBleaching catalyst (%) Example 5 Cyclic Fe complex (I-a-1) in 59production example 1 Example 6 Cyclic Fe complex (I-b-1) in 47production example 2 Example 7 Cyclic Fe complex (I-c-1) in 45production example 3 Example 8 Cyclic Fe comples (I-d-1) in 40production example 4 Comparative example 3 Fe-HM-DCB complex 27 offormula (8) Comparative example 4 Not added 16

1. A cyclic amide transition metal complex represented by formula (1)

wherein R¹, R², R³, R⁴, R⁵ and R⁶ are the same or different and each represent a hydrogen atom, a C1 to C16 hydrocarbon, a perfluoroalkyl group or a halogen atom, R⁷ represents an optionally substituted C1 to C18 alkylene or a perfluoroalkylene group, A represents a group having 1 to 3 quaternary ammonium groups substituted with a linear or branched alkyl group or linked with a linear or branched alkylene group, a cyclic quaternary ammonium group or a heterocyclic aromatic quaternary cation group which may be substituted with a linear or branched alkyl group, M represents a transition metal, L represents a ligand and Q represents an arbitrary counterion equilibrated stoichiometrically with a charge of the compound.
 2. The cyclic amide transition metal complex according to claim 1, wherein in formula (1), R¹, R², R³, R⁴, R⁵ and R⁶ each represent a methyl group, R⁷ represents a —CH₂)_(n)— group wherein n is an integer of 1 to 18, A represents —N⁺(CH₃)₂(C_(m)H_(2m+1)) wherein m is an integer of 1 to 18, —N⁺(CH₃)₂—(CH₂)_(p)—N⁺(CH₃)₃ wherein p is an integer of 1 to 18, or a pyridinium group, and M is Fe(III).
 3. A bleaching catalyst comprising the cyclic amide transition metal complex according to claim
 1. 4. A bleaching composition comprising (a) a bleaching catalyst comprising the cyclic amide transition metal complex according to claim 1 and (b) a peroxy bleaching agent selected from the group consisting of hydrogen peroxide and a peroxide or an organic peracid generating hydrogen peroxide in an aqueous solution thereof.
 5. A bleaching catalyst comprising the cyclic amide transition metal complex according to claim
 2. 6. A bleaching composition comprising (a) a bleaching catalyst comprising the cyclic amide transition metal complex according to claim 2 and (b) a peroxy bleaching agent selected from the group consisting of hydrogen peroxide and a peroxide or an organic peracid generating hydrogen peroxide in an aqueous solution thereof.
 7. A bleaching composition comprising the cyclic amide transition metal complex according to claim 1 and one or more additional agents.
 8. A bleaching composition comprising the cyclic amide transition metal complex according to claim 2 and one or more additional agents. 